“I really need to get there,” Prax said. He didn’t say, Every minute here is a minute that they could be hurting Mei. That she could be dying or getting shipped offworld. He tried to keep his words from sounding like a whine or a demand, but they seemed to come out as both.
“Getting ready’s the shitty part,” Amos said, as if agreeing to something. “You want to get right out into it right the f**k now. Get it over with.”
“Well, yes,” Prax said.
“I get that,” Amos said. “It’s no fun, but you’ve got to get through it. Going in without your gear ready, you might as well not go. Plus which the girl’s been gone for how long now?”
“Since the fighting. Since the mirror came down.”
“Chances of another hour making much difference are pretty small, right?”
“But—”
“Yeah,” Amos said with a sigh. “I know. This is the tough part. Not as bad as waiting for us to get back, though. That’s gonna suck even worse.”
Amos put down the swab and started fitting the long black spring back over the spindle of bright metal. The alcohol fumes of the cleaning solution stung Prax’s eyes.
“I’m waiting for you,” Prax said.
“Yeah, I know,” Amos said. “And I’ll make sure we’re real quick about it. The captain’s a real good guy, but he can get kind of distracted sometimes. I’ll keep him on point. No trouble.”
“No,” Prax said, “I don’t mean I’m waiting for you when you go to that door. I mean I’m waiting for you right now. I’m waiting to go there with you.”
Amos slid the spring and spindle into the shell of the gun, twisting it gently with his fingertips. Prax didn’t know when he’d risen to his feet.
“How many gunfights have you been in?” Amos asked. His voice was low and wide and gentle. “Because I’ve been in … shit. This’ll be eleven for me. Maybe twelve, if you count the one time when the guy got up again as a different fight. Point is, if you want your little girl safe, you don’t want her in a tunnel with a guy firing a gun who doesn’t know what he’s doing.”
As if in punctuation, Amos slid the gun together. The metal clacked.
“I’ll be fine,” Prax said, but his legs were trembling, just standing up. Amos held up the gun.
“This ready to fire?” Amos asked.
“Sorry?”
“If you pick this gun up right now, point it at a bad guy, pull the trigger, does it go bang? You just watched me put it together. Dangerous or safe?”
Prax opened his mouth, then closed it. An ache just behind his sternum grew a notch worse. Amos started to put the gun down.
“Safe,” Prax said.
“You sure about that, Doc?”
“You didn’t put any bullets in it. It’s safe.”
“You’re sure?”
“Yes.”
Amos frowned at the gun.
“Well, yeah, that’s right,” he said. “But you’re still not going.”
Voices came from the narrow hallway from the airlock. Jim Holden’s voice wasn’t what Prax had thought it would be. He’d expected him to be serious, grave. Instead, even during the times like now, when the distress clipped his vowels short and tightened his voice, there was a lightness to him. The woman’s voice — Naomi, not Cassandra—wasn’t deeper, but it was darker.
“Those are the numbers,” she said.
“They’re wrong,” Holden said, ducking into the mess. “They’ve got to be wrong. It doesn’t make sense.”
“What’s the word, Cap’n?” Amos asked.
“Security’s not going to be any use,” Holden said. “The locals are stretched too thin trying to keep the place from straight-out catastrophe.”
“Which is why maybe we shouldn’t be going in with guns drawn,” Naomi said.
“Please, can we not have that conversation again right now?”
Her mouth hardened and Amos pointedly looked at the gun, polishing the parts that already shone. Prax had the sense of walking in on a much longer conversation.
“This guy who grabs a gun first and talks later …” Naomi said. “You didn’t used to be him. You aren’t him.”
“Well, I need to be him today,” Holden said in a voice that closed the subject. The silence was uncomfortable.
“What’s wrong with the numbers?” Prax asked. Holden looked at him, confused. “You said there was something wrong with the numbers.”
“They’re saying that the death rate’s going up. But that’s got to be wrong. The fighting was … what? One day? Day and a half? Why would things be getting worse now?”
“No,” Prax said. “That’s right. It’s the cascade. It’ll get worse.”
“What’s the cascade?” Naomi asked. Amos slid the pistol into its box and hauled out a longer case. A shotgun maybe. His gaze was on Prax, waiting.
“It’s the basic obstacle of artificial ecosystems. In a normal evolutionary environment, there’s enough diversity to cushion the system when something catastrophic happens. That’s nature. Catastrophic things happen all the time. But nothing we can build has the depth. One thing goes wrong, and there’s only a few compensatory pathways that can step in. They get overstressed. Fall out of balance. When the next one fails, there are even fewer paths, and then they’re more stressed. It’s a simple complex system. That’s the technical name for it. Because it’s simple, it’s prone to cascades, and because it’s complex, you can’t predict what’s going to fail. Or how. It’s computationally impossible.”
Holden leaned against the wall, his arms folded. It was still odd, seeing him in person. He looked the same as he had on the screens, and he also didn’t.
“Ganymede Station,” Holden said, “is the most important food supply and agricultural center outside Earth and Mars. It can’t just collapse. They wouldn’t let it. People come here to have their babies, for God’s sake.”
Prax tilted his head. A day before, he wouldn’t have been able to explain this. For one thing, he wouldn’t have had the blood sugar to fuel thought. For another, he wouldn’t have had anyone to say it to. It was good to be able to think again, even if it was only so he could explain how bad things had become.